Internal combustion engine



Dec. 30, 1941;, ODMAN 2,268,532

INTERNAL COMBUSTION ENGINE Filed Feb. 12, 1941 4 Sheets-Sheet l 6 /9 6 b //////7V ,.l v

6 2 FIG I I 57 59 63 g E a l 6 t I 1 6 a a U 69 A -v//// m /////l\ 24 [lfl JOHN HOWARD GOODMAN INVENTOR ATTORNEY Dec. 30, 1941. J. H. GOODMAN INTERNAL COMBUSTION ENGINE {5941 4 Sheets-Sheet 3 N Filed F'e Joan Hbwmw Goonmm luvsnrol A'rronus Dec. 30, 1941.

4 Sheets-Sheet 4 Filed Feb. 12, 1941 FIG. 5]

INVENTOR m M m 6 M 6 3 R r 3 A E x 6 6 2 W M H H w I n v u W M F. w i J Q Q u I lall l fil l llrlllra l l hhln H n n 931 {I w Q w Q Q Q IO IQ \\\|IIIIII/ I//a/ lo 3 3 5 z a r 2 2 a 4 \Q I I a 11/ l Ill/I h! I/I I 8 Q r Patented Dec. 30, 1941 INTERNAL COIVIBUSTION ENGINE John Howard Goodman, Edgbaston, Birmingham, England Application February 12, 1941, Serial No. 378,639. In Great Britain January 30, 1940 4 Claims.

' vide an engine of the opposed piston type having greater simplicity in design, low manufacturing cost, improved balance, lighter weight and more compact dimensions for any given power. It'is also an object to increase mechanical efiiciency by reducing the number of main bearings required for a given number of cylinders. When the invention is applied to compression ignition 1 engines it has the further object of relieving the main bearings of most of the usual high pressure.

An internal combustion engine in accordance with the present invention has at least one pair of cylinders each cylinder containing opposed pistons with their piston rods connected to a pair of rock shafts on which rock shafts connecting rods to a crank shaft are provided said connecting rods from the rock shafts being arranged on the same side of a central plane containing the axes of the said rock shafts and of the crank shaft and being connected to two cranks on opposite sides of the shaft.

According to a preferred embodiment of the invention a number of open ended cylinders, i. e. cylinders open at both ends, are arranged in one or more groups of four, consisting of two pairs each one of a pair having its axis parallel to the other of the same pair, each pair of a group has its axis at right angles to the axes of the other pair of the same group; all these cylinders are arranged tangentially around a single central crank shaft, the axis of which is at right angles to the axes of the cylinders. The plane containing the axes of one pair of cylinders is spaced apart from, but parallel to, the plane containing the axes of any other pair of cylinders which are in effect duplicates of the first pair.

All the cylinders have two pistons each connected to rock shafts which are arranged equidistantly around the crank shaft, with their axes ,parallel to the same.

The crank shaft has two cranks (set at an angle which is less than 180) for each group of four cylinders and each crank pin is opera tively connected to four pistons, two of which work in cylinders located towards one side of the crank. andthe other two work in cylinders on the other side of the said crank.

The rock shafts are each provided with one double arm and one single arm, the double arm being preferably in one plane containing the axes of a pair of cylinders and the single arm working in another plane off-set far enough to enable .connection to be made with the crank pin in the space between the pairs of cylinders of each group of four.

The. appended drawings illustrate this convenient example in which groups of four pistons connected to two rock shafts are arranged about a single crank shaft with one group at right angles to the adjacent group.

Figure 1 is a central section with the two rock shafts and .arms shown in full; it is taken on the line a-a of Figure 2.

Figure 2 is asection on the line bb of Figure 1 looking in the direction of the arrows c.

Figure Sis a section on the line d-d of Figure 1 looking in the direction of the arrows c.

Figure 4 is an axial section showing a mounting of one of the rocktshafts.

Figure 5 is an elevation looking from the right 1 in Figure 2.

So far as many of the parts of the engine such 7 as the casings and mam shaft bearings are concerned these drawings are merely indicative and all parts may follow approved design. The present invention concerns the grouping of the cylinders with their opposed pistons around the shaft and the connection of the rocker arms or beams from opposed pistons to the shaft. Fuel pump or supply means and scavenging means are omitted from the drawings.

A pair of cylinders ll, l2, are arranged parallel to each other. The opposed pistons in cylinder II are marked I3, [4 and the pistons in-cylinder l2 are marked l5, [6. Between the cylind-ers is the crank shaft H at right angles to the members I8, 23 enclosing a crank chamber. Four'frame plates 18 and 23 of stout construction complete the main parts of the assembly which is bolted together by a series of bolts 24.

Covers I9 are fitted to the ends of these two casings l8 and 23, each cover extending not only over the casing containing the cylinders but also over the part facing the crank. chamber. Under each cover I9 is a space 20. The spaces 20 at the ends of cylinders H and I2 provide room for the rock shafts 21 around the sleeves 22 and for the working of the rocker arms or beams 25 to which are connected the piston rods 26,21,28 and 29 from pistons l3, l4, l5 and i6 respectively. In the part over the crank chamber 33v further arms 30 are carried from each rock shaft 2| and on these the connecting rods 3|, :32 are hinged and enter the chamber 33 where the two crank pins 34 and 35 are mounted on-the crank shaft 11.

In the second pair of cylinders is another group of four pistons corresponding exactly: with 26 to 29 so that there is no need to particularise them or illustrate them. Theirpiston rods 53,

54,55, 56 are seen in Figure lconnected to the rocker arms 51 on the barrel shaft 58. Further along the rock shafts 58 are the arms- 59and 60 on which the two connecting rods (iiv and 62 for connecting the rockshafts with'the crank pins 34 and 35 are'mounted.

The cranks are preferablyset at anangle of about 140 degrees. The actuaLangle depends on the distance apart of the cylinders, the lengthof stroke and the .positionsof the rock shafts, but

it is determined by the fact that the arrangement :2 is such that bothcranks are in the dead centre positions simultaneously, The: crank shaft. pins 34 and 35 are each made longenoughto take of the other pair of cylinders l i and 12, are simi-' r-.

larly connected by the non-forked connectin rod.3| tothefirstcrank-pin 34 ,andvbytherother connectingrod 32 .to thesecond crank pin 35.

.Thus itwill .be seen that the four connecting rods work .at approximately right angles ,to each other, see Figure 3.

.Due to :the fact that the two connecting rods from the .one. pair of cylindersand their respective arms onthe rock shafts (e..,g. rods 3!, 32 and arms30, Figure 2) are bothlarranged on the same side of the central plan containing the rock shafts 2i and the ,crank shaft l 'l, better relative .movementsof the opposed pistons and a better balance are obtained. The same is true of I the connecting rods BI, 62, from the arms 59. 60

and rock shafts 58 of the other pair of cylinders as the arrangement is similar to that of the first pair turned through a right angle.

Owing to the connecting rods being arranged .so that the one from the rock shaft at one end of a pair of cylinders leads to the first crankpin while that from the other end leads to the other crank pin, each crank pin is only subjected'to the maximum pressure 1' from one piston'at' a time, thus effecting a considerable 'saving'inthe awhile havingall the thermodynamic advantages of. opposed pistons; thus it is very suitable for use in aircraft.

'1. An'internal combustion engine comprising in combination a pair of cylinders arranged parallel to each other with one of the pair on each side of a. crank shaft; a similar pair of cylinders arranged one-on each side .of-the said crankshaft but with their axes .at right angles tothose ofthe first mentioned pairetwo opposed pistons in each of :said cylindersand a rod from .each piston to an .arm on a rock shaft-at the vendof the cylinder,

'- the rock shafts .beingxfourin number disposed equally around .said crank shaft :at the ends :of

. at least on pair of' cylinders each cylinder provided rwithroppositely :-working piston rods I from the pistons thereinto rock shafts at the ends of the cylinders, a single crank shaftbetween the cylinders with -,twocranks rat-an. angle to each other of approximately degrees, 'aconnecting rod from each rock; shaft to the crank; shaft, said I connecting rods from two-diametrically opposed rock shaftsbeing connected "one .to jeachecrank vand being connected 130111116 rock shafts on the same side of ;a plane containing ,thez-axes .ofthe rockshaf-taandthe crankshaft axis.

'3. An-.-interna1 combustion enginehaving at least two pairs. of cylinders each. of which pairs is spaced from. thegotherpairs each10f said cylinders c n nin ep edyp t n in piston rods,- -the cylinders-of .eachpair-being parallelv to each other :and .onropposite .sides of: t e. crank shaft-and the cylindersofone pair'being-at right angles to those .of the rad-jacentrpair, the axes of .all of the cylinders being. at rightzangles ,toathe axis of the crank shaft, founrockshafts eachof which isv at one end of .a pair of= cylinders,x said rock, shafts: being spaced at equiedistant points aroundthe crankshaft, a rocker,arm on eachof least two pairsof cylinders each 'of which pairsis spaced from the other pairs, each of said cylinders containing *opposeT-pistons having piston rods, the'cy'linders of each; pair being parallel to each other and on opposite sides of "the crank shaft'and the cylinders of-one pair being at'right angles to those of the other-"pairs," the axes-20f all of the cylinders being at right=anglesto the+axis rock shafts to the crank shaft, all of said additional rocker arms being arranged in the space between the two pairs of cylinders, the crank shaft ends of two of said connecting rods being forked and the corresponding ends of the other two connecting rods being connected to the crank shaft inside said forked ends.

JOHN HOWARD GOODMAN. 

